A passenger jet flies past the FAA control tower at Washington's Ronald Reagan National Airport in 2011.

Cliff Owen/AP

Unless Congress acts, across-the-board spending cuts scheduled to take effect March 1 will be felt throughout the government. Some of the most visible effects will be noticed by air travelers.

Officials predict that cutbacks at the Federal Aviation Administration could lead to takeoff delays and fewer flights overall.

The FAA's work is done largely out of public view, in airport control towers and regional radar centers, in hangars and workshops. But if the spending cuts, known in Washington-speak as sequestration, start taking effect on schedule, the importance of that backstage work will move front and center.

Danny Werfel of the Office of Management and Budget said at a Senate hearing last week that the sequester will take a toll at the FAA.

"FAA is going to face a cut of roughly $600 million under sequester," Werfel said. "A vast majority of their 47,000 employees will be furloughed for one day per pay period for the rest of the year, and, as importantly, this is going to reduce air traffic levels across the country, causing delays and disruptions for all travelers."

In a letter to agency employees, FAA Administrator Michael Huerta said the temporary layoffs would require "a reduction in FAA services to levels that can be safely managed by remaining staff."

Marion Blakey, who used to head the FAA and is now CEO of the Aerospace Industries Association, says she agrees cutbacks will not go unnoticed.

"If sequestration goes into effect, level-headed people all over this town, all over Washington, are saying, 'Yes, it will have a major effect on the aviation system,' " she says. "And this isn't doomsday; this isn't some sort of science-fiction plot that we're all talking about. This is reality, and it's reality coming up next month."

Blakey says more than 2,000 air traffic controllers will be furloughed at one time or another, and there will be ripple effects.

"It's one of those things that when you start cutting back on service, it affects even community airports, because, after all, they don't have the flights coming in," she says. "The landing fees, the concessions, the parking lot — all of those sources of revenue suffer."

Blakey says that could mean an annual loss of $1 billion in tax revenues.

It's not only controllers who face furloughs. There are thousands of FAA technicians, who fix equipment such as radar and navigation systems.

Mike Perrone, president of the Professional Aviation Safety Specialists, the union that represents them, says furloughed technicians may mean slower repairs on things like instrument landing systems, or ILS.

"For example, if you're flying into, let's say, Chicago, and their primary runway ILS was down because they couldn't get it certified, then now that creates delays," he explains. "They have to go to an alternate runway or maybe an alternate airport."

The sequester's impact may depend on how it's implemented.

Robert Poole of Reason Foundation, a libertarian group, says it would be less damaging if the FAA were able to cut the capital budget for construction, say, rather than the operating budget.

That way, it could cut "the facilities and technology and that sort of thing, as a short-term measure to preserve the operations and keep everybody employed, keep ... all the towers operational, all the centers operational and minimize the impact on the traveling public."

It's not clear whether the FAA has much flexibility to shift funds from one account to another. But the agency says it will do what it can to limit furloughs.